Trouble with apple ID

For the past year I haven't been able to log into itunes because I'm just never able to. Today I was able to change my password through my phone so that I could cancel a subscription of some sort, and when I tried to log in on my computer it keeps saying password is incorrect. I even used a verification code I was sent on my phone and it doesn't work on any of the apps on my computer. Why is this happening and what do I do??😕